Crate irox_structs

source ·
Expand description

A very simple ‘Struct’ library that provides a single trait. This is intended to be most generally used in concert with irox_structs_derive to generate the impls.

A Struct is a linear sequence in memory of serialized bytes - serialized in the order the fields are present in the struct with no adjacency or packing.

§Strict Sizing

By default, irox_structs_derive will allow variably sized types like String and Vec<u8>. If you know you don’t need/use these, apply a #[strict_sizing] attribute, and the generator will add a pub const STRUCT_SIZE: usize to the struct

§Choosing Endianness:

Apply either the #[big_endian] or #[little_endian] attributes when deriving Struct and it will use the appropriate serializers. If not specified, it defaults to big endian.

§Example Big Endian:

use irox_structs::Struct;
use irox_bits::Error;

#[derive(Default, Debug, Copy, Clone, Eq, PartialEq, Struct)]
#[strict_sizing]
pub struct UdpHeader {
    source_port: u16,
    dest_port: u16,
    length: u16,
    checksum: u16,
}

pub fn main() -> Result<(), Error>{
    assert_eq!(8, UdpHeader::STRUCT_SIZE);

   let header = UdpHeader {
        source_port: 0x0064,
        dest_port: 0x0400,
        length: 0x1388,
        checksum: 0x01C2,
    };
   let mut output_buf: Vec<u8> = Vec::new();

   header.write_to(&mut output_buf)?;
   assert_eq!(output_buf.len(), 8);
   assert_eq!(&[0x00u8, 0x64, 0x04, 0x00, 0x13, 0x88, 0x01, 0xC2],
                output_buf.as_slice());

   let parsed = UdpHeader::parse_from(&mut output_buf.as_slice())?;
    assert_eq!(header, parsed);
 Ok(())
}

§Example Little Endian:

use irox_structs::Struct;
use irox_bits::Error;

#[derive(Default, Debug, Copy, Clone, Eq, PartialEq, Struct)]
#[little_endian]
#[strict_sizing]
pub struct UdpHeader {
    source_port: u16,
    dest_port: u16,
    length: u16,
    checksum: u16,
}

pub fn main() -> Result<(), Error>{
    assert_eq!(8, UdpHeader::STRUCT_SIZE);
   let header = UdpHeader {
        source_port: 0x0064,
        dest_port: 0x0400,
        length: 0x1388,
        checksum: 0x01C2,
    };
   let mut output_buf: Vec<u8> = Vec::new();

   header.write_to(&mut output_buf)?;
   assert_eq!(output_buf.len(), 8);
   assert_eq!(&[0x64u8, 0x00, 0x00, 0x04, 0x88, 0x13, 0xC2, 0x01],
                output_buf.as_slice());

   let parsed = UdpHeader::parse_from(&mut output_buf.as_slice())?;
    assert_eq!(header, parsed);
 Ok(())
}

Traits§

  • Bits
    Read methods for the primitive types
  • MutBits
    Write methods for the primitive types
  • Struct
    A struct is a series of bytes in memory, serialized in the order that the fields are present in the struct.

Type Aliases§

Derive Macros§